I own a Marshall ‘72 Super Bass (model 1992) which has been converted to late-‘60s Plexi-era Super Lead specs.

I have owned the amp for almost 11 years; it was sold to me as having all-original transformers and choke, and I have never had any reason to question that fact. I see no evidence whatsoever of either if transformer or the choke ever having been replaced or otherwise tampered with.

However...now that I am considering selling or trading the amp, I am getting questions about verifying that those parts are all original. There are no ink-stamped codes on either transformer or the choke. I have seen countless photos of vintage Marshall Super Bass and Super Lead amps in which the transformers and choke look EXACTLY like mine, also without numbers stamped or any other identifying marks/stamps. I have also seen a very small few amp which DO have a stamped code on at least one of the transformers; this appears to be much more rare than amps with no stamped codes.

For prospective buyers, and so I am NOT misrepresenting the amp, how can I verify either way whether the transformers and choke are in fact all original?